Parameter Channel - WAGO I/O-SYSTEM 750 Manual

WAGO-I/O-SYSTEM 750
®
750-644 Bluetooth RF-Transceiver
Table 36: Status byte S
Bit 7
1
REG_NO
All register communication processes follow the request/response principle:
1. A request is made in the output process image (PIO). This can be generated
by a PLC application, for example.
2. The I/O module generates a response in the input process image (PII).
There is a request when the value of REG_NO or RW changes in the PIO
compared to the previous status or register communication is remapped. If write
access is involved, the I/O module also processes bytes D0 and D1 of the PIO as
new values for register REG_NO.
There is a response when the value of REG_NO or D0 or D1 changes in the PII
compared to the previous status. If it involves read access in the previous request,
the D0 and D1 bytes then receive the current value of the REG_NO register.
6.3.4

Parameter Channel

Some I/O modules of the 750 series offer a protocol subsequently referred to as
"parameter channel" for the configuration. Parameter channel provides read
and/or write access to up to 256 parameters, i.e. data words of the respective I/O
module. The protocol allows, for example, data exchange between the 750-644
I/O module and a PLC application.
The parameter channel uses register communication to transport data:
• Register 56: Parameter data is stored here word by word.
• Register 57: Communication is controlled for the data.
The basic sequence for reading a parameter is:
1. Write register 57 with the read request command.
2. Read register 57 to check the execution status.
3. If the read request was successful: Read register 56 to obtain the requested
data.
Manual
Version 2.0.0, valid from FW/HW Version 03/03
Bit 6 Bit 5
0
Register number (e.g. 56 or 57)
Status byte S
Bit 4 Bit 3
REG_NO
Process Image
Bit 2 Bit 1
61
Bit 0